Carburetor for internal combustion engines



March l5, 1960 P. AUGUST CARBURETOR FOR INTERNAL COMBUSTION ENGINES Filed April 1, 1958 2 Sheets-Sheet 1 Fia] INVENTOR.

PABLO Ausl/5r 7'0 SOL/RCE UFO/L MPU? 1 a 1 1 NE Marc-h l5, 1960 P. AUGUST 2,928,662

` CARBURETOR FOR INTERNAL COMBUSTION ENGINES Filed April 1, 1958 2 Sheets-Sheet 2 INVENTOR.

y PABLO AUGUST BY mmv 757mm A7' TOR/VEYS ilnited States Patent@ CARBURETOR FOR INTERNAL COMBUSTION ENGlNES Pablo August, Buenos Aires, Argentina Application April 1, 1958, Serial No. 725,589 I 11 Claims. (Cl. 26141) This application is a continuation-'impart of my copending application Serial No. 598,811, tiled July 19, 1956 and now abandoned, wherein I have described an improved carburetor for internal combustion engines `comprising a shut-off device for immediately interrupting the fuel supply to the engine when the throttle valve is closed.

My present invention refers to certain further new and useful improvements in carburetors aiming at not only economizing fuel, but also avoiding a dilution ofthe lubricating oil in the working cylinders and ensuring a perfect lubrication of the working pistons and cylinder even when, for instance, Va motor car moves down hill and drives the motor.

The main object of my invention is'to provide an improved carburetory for internal .combustion engines comprising in combination with a mechanically operated .shutoff device provided in the main fuel system a. vacuumf operated shut-olf device in the idling systemY connected with a source of oil-saturated airand so arranged that when closing the throttle valve, the fuel supply Vis practically at the same time interrupted in both the main fuel system and the idling system and during these periods of fuel-supply interruptions oil-saturated airfor lubricating the working piston and cylinder is vsucked-in by the engine as long as it continues operating.

One object Vof the invention is to-provide an improved carburetor, comprising in its main fuel system a mixing tube in communication with the usual oat chamber, provided rwith fuel-outlet ports Vand with an air-inlet springloaded nozzle member movably arranged in said mixing er" f 1@ 2,928,662

Fig. 1 is a schematic vertical sectional view of a carburetor for internal combustion engines according to the invention `incorporating vshut-off devices for interrupting the yfuel supply through both the main fuel system and the idling system of the carburetor; in this figure the known .parts of the idling system have been omitted and only 'the novel shut-off device of the same has been shown;

Y Figures 2 and 3 are two enlarged vertical sectional views 'of the shut-olf device of the idling system in two different embodiments of the invention;

Figure 4 `is a cross sectional view along the line of Figure 2;

, Figure 5 is an elevation of the carburetor as seen from behind, showing the mechanical connection between the usual .throttle valve of the carburetor and the control -means of the shut-off device of the main fuel system.

. The main fuel system of the carburetor comprises a mixing chamber 1 with theair inlet Z, the venturi tube 3 and the air outlet 4 containing the usual throttle valveS. i

The mixing chamber 1 contains a tubular supporting member 6 which is Aclosed at its lower end and into which at 7 opens a fuel-supply channel from the oatchamber 8, said supporting member carrying a mixing tube 9.

tube for closing said outlet ports, a lever means operative v cumferential groove of said piston and being under the control of this piston which on the one hand is operated by a spring Amember and on the other hand by a partial vacuum produced by the engine, with the advantageous result that when the usualthrottle valve vof the carburetor is .closed thesaid spring-.loaded nozzle andthe said control piston are moved to their fuel-shut-oti` position in .which this control piston at the same' time'opens aconection with a source of oil-saturated air and permits lower packing ring 29.

throughthe upper ring member 26 and is surrounded by V .aheiical spring 31, the pressure of which Vmay be regulat- -of a mixing nozzle 15. The upper end of this nozzle -conveniently comprises inserted therein a throttle mem- .ber 16, whereas its lower Vend Vcarries a perforated tube formed as a tubular extension 16' of smaller diameter. Whereas'the nozzle member 15 snugly tits in the upper portion of the tube 9, lsaid Vtubular extension V16 freely .projects into the lower rportion of said tube 9. The arrangement of the nozzle member 15 is such that it is normally held in its rlifted position .as shown maintaining the outlet ports 10 open, but closed these ports when it is moved down-wards by means of a lever 17 until Vresting on -the 'shoulder 11.

The lever -17 is secured to a .shaft 18 which at the outside has .fixedlymounted thereon an arm 19 (Fig. 5), andthis arm 19 is connected by a rod member 20 with an ,arm 21 secured to the shaft 22 in-such an arrangement that when the throttle valve 5 is closed in the usual .manner the lever 17 moves the nozzle member 15 downwards, closes the fuel-outlet ports 10 and thus instantaneously shuts-off the fuel supplythrough the main system of the carburetor.

The idlingsystem has not been'` shown in as far as details of known construction are concerned. The shutotr' device of said system according to the invention comprises a casingV 23 (Fig. 2) which conveniently forms vpart of the carburetor body .1 (Fig. 5) and has a cyv l linder 24 inserted and fixed therein. The cylinder 24 contains a movable piston 25, an upper ring member 26 and" a lower ring member 27, an upper packing ring v28 and a The .piston -rod 30 extends ed by a screw 3Zin combination with a washer 33. The top surface of the piston 25 cooperates with the upper packing-ring 2S to make a tight seal in its `upper position.

the engine while still running to suckin such oil-.saturated I air for lubrication purposes.

With these objects and .advantageous features in view my present invention comprises the arrangement, combination and construction of parts as will be hereinafter fully described with particular 'reference to Vthe accompanying drawings, wherein: f

The lower end of the piston 25 is formed with a conical' recess so as :to provide an annular surface'34 capable'of making lan air-tight seal with the packing ring 29.

Thechamber 35 is'permanently communicated through the ringmember 27 and a channel 36 (Fig. l) with the Patented Mar. 15, 1960 "in Figures 2 and'3 is very eicient. i the idling system must have an inner diameter of `3-3.5

duced by piston of the working cylinder will become.

effective in the chamber 35 `and will cause the piston 25 to move from its upper to its lower position.

The reference numeral 37 (Fig. 4) indicates the fuel channel of the idling system. The channel 37 registers with a transversal slot 38 of the'cylinder 24 which comprises a similar slot 39 at a substantially diametrically opposite point. This second slot 39 is :in communication with a tangential channel 40 and the two slots 38, 39 are interconnected by a circumferential groove 41 of the piston 25, the arrangement being such that, when the piston 25 is in its upper position as shown, the fuel supplied by the usual mixing nozzle of the idling system -(not shown) may freely pass by way of vsaid groove 41 to the working cylinder of the engine. l

Below the slot 39 there is provided `a channel 42 and the groove 41 is so broad that', when the piston 25 is in its lower position, it will interconnect the chanf shown inFig. 2.

The channel 42 is connected by means of a pipe member V43 with a suitable source of oilivapor or oil saturated air such as the crank case of the engine, the

'arrangement beingsuch that when the piston 25 is in its lower position and interrupts the fuel supply through theidling system, the engine will suck in oil vapori:v

or oil-saturated air by way the pipe 43, channel 42,

groove 41 and fuel-outlet channel 40.

The embodiment as shown in' Fig. 3 differs from that of Fig. 2 insofar as the channel 42 is omitted and a channel 44 connects the channel 40 with the interior of the cylinder 24 'at short distancefrom the upper ring t member 26. In this arrangement the two slots 38, 39

are situated at substantially the same level. Further, in this embodiment the upper ring Vmember 26 carries a tube 45 conveniently of transparent material inserted i into an upper extension of the cylinder 24 and provided at its upper end with a neck portion 46 for the connection of a rubber hose (not shown) leading to a suitable source of oil vapor or oil-saturated air (not shown), the arrangement being such that, when the piston 25 is in its lower position and interrupts the fuel supply through the idling system, the engine will suck in oil vapor or oil-satu- -rated air by Way of the tube 45, the annular space between piston rod 30 and ring member 26, channel 44 and fuel-outlet channel 40, and that said oil vapor or oil-saturated air will perfectly lubricate the engine,

its idling system are closed, but the engineV continues running for being operated by the car.

The shut-0E device of the idling system as shown The channels of Y of the latter may be reduced to 1 mm. and the piston stroke to 1.5 mm. only. AIn this manner my present invention provides avery eicient-and exactly operating The operation ofthe improved carburetor according` to my present invention vis shortly as follows:

As soon asthe driver of a car' closes theV throttle valve 5, by means of the Ymechanical connection com- .'prising the arm 21, rod 20, arm 19, shaft 18 and lever l 17, the nozzle 15 is moved downwards and closes-the fi fueloutlet ports 10 thereby interrupting the fuel supply -through the main fuel system of the carburetor. Simultaneously the suction produced by the working piston of vengine receives the required oil for its lubrication, for

instance, when the car moves down-hill and operates the engine.

What I claim as new and desire to secure by Letters Patent is:

l. A carburetor with a float chamber, a main fuel system and an idling system for internal combustion engines, comprising a mixing chamber with an air inlet, a venturi tube formed in said chamber, a fuel nozzle connected with said float chamber and surrounded by said venturi tube, and a mixture outlet containing the usual throttle and having a iiange for its connection with the intake of an internal combustion engine, a rst fuelshut-olf device provided `in connection withl said fuel nozzle in said main fuel system and a second fuel-shut-off device in said idling system, both of said shut-off devicesV being dependent of the operation of the throttle valve in said mixture outlet, said second shut-otfvdevice comprising a cylinder having a piston-like valve body .movably arranged therein, there being channels in the wall of said cylinder and in said piston controlled by the latter and capable of communicating said float chamber with an outlet of said idling system connected in turn with said mixture outlet of said mixing chamber with said float chamber, respectively with an intake port of said cylinder for oil-saturated air.

2. VA carburetorl with ,a float chamber, a main fuel -system and an idling system for internal'combustion engines, comprising a mixing chamber with an air inlet, a venturi tube formed in said chamber, a fuel nozzle-connected with said float chamber and surrounded by said venturi tube, and a mixture outlet containing Anozzle in said main fuel system and a Vsecond fuelfuelshut-oif device provided in connection with said fuel shut-olf device in said idling system, both Aof said shutoff devices 'being dependent on the operation of the -throttle valve in said mixture-outlet, the shut-off devic'e-offsaid main fuel system comprising a mixing tube 'having'a movable spring-loaded nozzle member arranged therein, there being fuel-outlet ports in said mixing tube and controlled by said Vnozzle member, a lever operatively connected by a mechanical motion-transmitting system 'with said'throttle for controlling said nozzle member, said second shut-olf device comprising Va cylinderhaving a piston-like valve body movably` arranged therein, there being channelsin the wall of `said cylinder l and 'in said piston controlled by therlatterl and capable of `communicating said floatchamber with an outlet of said idling 'system connected in turn with said mixture outlet of said mixing chamber with said float chamber, respectively with an intake port of said cylinder for oilsaturated air.`

3. vA carburetor for internal combustion engines as set forth in claim 2, wherein the said spring-loaded nozzle membercomprises a main .tubular upper portion for controlling' thesaidfuel-outlet ports'of the said `mixsing" tube", land alperforated'tubular extension ofsmaller shut-off device capable of`reduc'ing the fuel consump- -Y tion'of the engine. f

' forth in claim 2, wherein the spring-loaded nozzle mem- Y ber includes' a throttle member arranged within,` the upper free end of the same.

" 5. A carburetor for internal combustionengines as set forthin claim 2, whereinv the said'piston-like valve body comprises a circumferential groove' and the said cylinder containing said piston is provided with transversal` slots in direct communication with .tangential fuel-inlet and outlet channels of the said idling system, said tangential channels being formed in the walls of a casing surrounding said cylinder.

6. A carburetor for internal combustion engines as set forth in claim 2, wherein the said inlet port for an oil-saturated air is connected with the outlet of the idling system by way of a perforation of a casing surrounding the said cylinder of the said shut-off device of said idling system and of a registering perforation of said cylinder which in turn is connected with said outlet by way of a circumferential groove of the said piston in said cylinder when said piston is in its lower position.

7. A carburetor for internal combustion engines as set forth in claim 2, wherein the said inlet port for an oil-saturated air is formed by a neck portion of a tube surrounding the rod of the said vacuum-operated piston and being in turn connected with the outlet of the said idling system by way of the interior of the said cylinder containing said piston and of a channel formed in the walls of said cylinder and of a casing surrounding the latter.

8. A fuel-shut-oi device for the idling system of carburetors for internal combustion engines, comprising a cylinder connected with the fuel inlet and outlet of said idling system, a vacuum-operated spring-loaded piston in said cylinder for controlling said inlet and outlet, a pair of relatively long and narrow transversal slots provided in the wall of said cylinder within reach of a circumferential groove of said piston and a pair of channels arranged in tangential relation to said slots and in direct communication with the latter, said channels forming parts of said fuel inlet and outlet.

9. A fuel-shut-ol device for the idling system of carburetors for internal combustion engines, comprising a cylinder, a pair of substantially opposite transversal relatively long and narrow slots provided in the wall of said cylinder for its connection' with the fuel inlet and outlet of said idling system, a vacuum-operated springloaded piston in said cylinder for alternatively closing said slots and interconnecting the latter by way of a circumferential groove ofthe piston body, a pair of ring members fixed in the open ends of said cylinder and provided respectively for the protrusion of a-rod of said piston and for the communication of the interior of said cylinder with a suction channel leading to the outlet of the carburetor below its throttle valve, and a pair of packing rings arranged on the inner surfaces of said ring members for co-operation with said piston in air-tight sealing the cylinder ends.

10. A fuel-shut-oi device for the idling systems of carburetors for internal combustion engines, comprising a cylinder having open ends and being provided with a pair of substantially opposite relatively long and narrow slots cut into the wall of said cylinder for its connection with a pair of channels leading tangentially to said slots and forming parts of the fuel inlet and outlet of said idling system, a vacuum-operated spring-loaded piston arranged in said cylinder and provided with a circumferential groove for interconnecting said slots, a pair of ring members fixed in the open ends of said cylinder and a pair of packing rings provided on the inner surfaces of said ring members for cooperation with said piston in air-tight sealing said cylinder ends, one of said slots which is in direct communication with the fuel-outlet channel being arranged on a slightly lower level than the other slot connected with the fuel-inlet channel, and an opening provided in the cylinder wall at short distance below said firsbrnentioned slot, the said circumferential groove of said piston beingY of suiiicient width to alternatively interconnect saidrtwo slots and said rst-mentioned slot with said opening.

l1. A fuel-shut-off device for the idling systemvof carburetors for internal combustion engines, comprising a cylinder having open ends and being provided with a pair of substantially opposite relatively long and narrow slots cut into the wall of said cylinder for its connection with a pair of channels leading tangentially to said slots and forming parts of the fuel inlet and outiet of said idling system, a vacuum-operated springloaded piston arranged in said cylinder and provided with a circumferential groove for interconnecting said siots, a pair of ring members fixed in the open ends of said cylinder and a pair of packing rings provided on the inner surfaces of said ring members for co-operation with said piston in air-tight sealing said cylinder ends, said channel forming part of the fuel-inlet of the idling system being connected by way of secondary channel with the interior of said cylinder at a point near its upper end slightly Ybelow its upper ring member.

References Cited in the le of this patent UNITED STATES PATENTS 1,967,352 Y Earle July 24, 1934 2,212,936 Hoof Aug. 27, 1940 2,386,340 Olson Oct.l 9, 1945 2,737,935 Olson Mar. 13, 195.6

K FOREIGN PATENTS Y l 800,897 France Mar. 1l, 1936 

